Drill pipe protector



May 2 8, 1935. c. K. HoL'r ET'AL 2$02,893

DRILL PIPE PROTECTOR I Originalv Filed May 19, 1953 2, Sheets-Sheet l May 28, 1935 c. K. HoLT AL 2,002,893 i DRILL PIPE PROTECTOR v Original Filed May 19, 1933 2 Sheets-Sheet 2 'PatentedMay 2s, 1935 UNITED STATES DRILL PIPE PROTECTOR Charles K. Holt, Santa Barbara, Ira B. Marsh, Ventura, and John B. Merritt, Santa Barbara,

. Calif.

Application May 19, 1933, Serial No. 671,880 Renewed November 5, 1934 14 Claims.

bearing device for use /on a rotary well drilling string. It is a general object of the present invention to provide a simple, practical and effective drill pipe protector.

In the rotary method of well drilling, the drilling tool is operated on the lower vend of an operatng string -made up of lengths of'drill pipe connected by couplings and tool joints. A deep well is seldomA straight and vertical and when the drilling string'vor operating string is rotated, it engages the well casing and the walls of the open well bore, with the result that vthe couplings and joints in the string become worn, and the well casing is damaged. Devices known as casing protectors or drill pipe protectors are often arranged on a rotary drilling string to prevent excessive wearing of the casing and parts of the string, and to centralize the string in the well. The majority of the drill pipe protectors that have been introduced have been complicated and are not altogether satisfactory in operation, as they have been constructed with the intention of being immovablyxed on the drilling string. Drill pipe protectors of the class just mentioned are usually diiiicilt to assemble on the drilling string and are often sectional so that they are subject to failure and detachment from the string. A class Aof drill pipe protectors has been developed in which the body is proportioned so as to be movable on the drill pipe between spaced couplings of the string, but cannot be sprung over the couplings, so that its arrangement on the string lnecessitates the disconnection of a coupling from a length of drill pipe. The typesy of drill pipe protectors that are free to shift on the drill pipe.

are of greater specific gravity than the circulation fluid or rotary mud so that they slide down the string and rest on the upper ends of the couplings or joints and do not protect the lower ends of the couplings or joints which are the most subject to wear.

An object of the present invention is to provide a drill protector that may be easily and quckly arranged on a drilling string between spaced projecting parts in a manner so that it cannot become displaced or shifted from its position between said parts.

Another object of the invention is to provide a drill pipe protector that has a lower specific gravity than/ the usualI rotary mud and that is free to shift on the drilling string between spaced couplings, or the like, so that it may float up against a coupling and effectually prevent its engagement with the well casing or wall of the well bore. v

Another object of the invention is to provide a drill pipe protector that may be free to turn 4and/or shift longitudinally between two project- (ci. 30s-4) ing parts on a drilling string, but cannot possi-l bly become displaced from between the projecting parts. It has been found that a drill pipe protector operates more efficiently when it is free to move on the drilling string, but considerable difficulty has been encountered in providing a drill pipe protector that is free to turn or shift on the pipe and which will not become displaced from its proper position on the pipe. In accordance with the present invention, the drill pipe protector is free to turn and to shift between two spaced projecting parts on the drilling string but cannot possibly become displaced from its proper position on the string.

Another object of the invention is to provide a drill pipe protector of the character mentioned that includes a continuous or unbroken body of resilient wear-resisting material projecting from the drilling string and adapted to engage the wall of the well bore or the well casing, thereby preventing contact of adjacent couplings or tool joints with the walls Vof the well or with the well casing.

Another object of the invention is to provide a drill pipe protector including an annular or tubular body of resilient wear-resisting material such as a rubber composition, and a sectional substantially rigid core or reinforcement embedded in said resilient body whose sections may be disconnected or unlocked at adjacent edges, to permit the resilient body to be expanded and sprung over a shoulder or coupling on the drilling string, and thereafter dependably locked together to prevent expansion of the resilient body so that the body may be eiectively and positively retained between two such shoulders or couplings on the string.

It is another object of the invention to provide a casing protector or drill pipe protector including an annular to tubular body of rubber composition or othen resilient material presenting a continuous or unbroken outer surface for contacting with the well casing or wellbore, and a rigid or substantially unyielding reinforcement entirely embedded in the resilient body.

Another object of the invention is to provide a drill pipe protector of the character mentioned that is simple and inexpensive of manufacture.

Other objects and features of the invention will be best and fully understood from the following detailed description of typical forms and applications of the invention, throughout which description, reference is had to the accompanying drawings, in which:

lFig. 1 illustrates one embodiment of thev prese t invention arranged on a sub or connecting member in a portion of a drilling string operating in a well bore. Fig. 2 is an enlarged vertical detailed sectional view of the form of the invention illustrated in Fig. 1, showing it arranged on another form of sub. Fig. 3 is a view similar to Fig. 2 illustrating the manner of passing or springing the body of the protector over one of the shoulders of the sub. Fig. 4 is a transverse detailed sectional viewtaken as indicated by line 4 4 on Fig. 2. Fig. 5 is a prospective view of the core or reinforcement. Fig. 6 illustrates the protector mounted on a length of 'drill pipe between two couplings. Fig, 7 is a front elevation of a form of reinforcement involving a modified type of pin for locking together the sections of the reinforcement, and Fig. 8 is a fragmentary longitudinal detailed sectional view of another form of the invention.

The embodiment of the invention illustrated in Figs. 1 to 5 inclusive of the drawings, includesI generally, a sectional annular reinforcing core or reinforcement Ill, means II for connecting the sections of the reinforcement In, and a continuous or unbroken annular body I2 of resilient material surrounding or encasing the reinforcement I0.

The reinforcement IIl is an annular or tubular accordance with the broader aspects of the invention, the reinforcement IB may consist of any suitable number of sections. In the particular form Aof the invention being described, there are two like or complementary sections I3 forming the reinforcement I0.

'I'he sections I3 are preferably formed of a light weight sheetl metal such as sheet duraluminum, or the like. The sections I3 are of a suitable gage and are preferably sufficiently rigid when connected by the means II to effectively strengthen and reinforce the body I2. The two sections I3 of the reinforcement are each substantially 180 in horizontal cross section so that they form a tube or tubular structure when assembled. The reinforcing core or reinforcement I is of a suitable length, its length of course, depending upon the length of the body I-2. In accordance with the invention, the sections I3 of the reinforcement I0 are perforated or provided with a plurality of spaced openings. In the particular case illustrated in the drawings, each section I3 is provided with a multiplicity of spaced round openings'l4, and a plurality of comparatively large openings I5. The openings I are varied in size, andare rectangular or diamond shaped and positioned so that their greatest diagonal dimensions extend longitudinally of the sections I3. The openings I 4 and I5 are provided in the sections 4I 3 to lighten the reinforcement IIJ and to insure a more perfect bond or connection between the material forming the body I2 and the sections I3 as will be more fully described.

The means I I is provided to rigidly connect the adjacent vertical edges of the two reinforcing sections I3. In `Vthe form of the invention being described, the means II are releasable. The means II include meshing or overlapping parts I'I on the adjacent vertical edges of the two reinforcing sections I3. The meshing or over-lapping parts I1 are preferably integral with the sections I3 and the material forming the parts' I'I is looped or bent back upon itself to provide vertical `openings I8 through the parts I1. The openings I8 may be horizontally elongated and may have substantially parallel vertical side walls. The material constituting the meshing parts I1 is bent inwardly against the inner sides of the sections I'I and the abutting parts are connected by rivets I9, or thelike. The openings I8 on each set or series of meshing parts II are in vertical alignment when the two sections I3 are assembled as illustrated throughout the drawings. In the particular construction being described, the' parts I1 have suitable clearance with one another and notches 20 are provided in the vertical edges of the sections I3 between the spaced parts Il.

Pins 22 normally extend through the openings I8' of the two sets or over-lapping parts Il to rigidly connect the two reinforcing sections I3. In accordance with the invention, the pins 22 are adapted to be passed through the sets of openings I8 to connect the adjacent vertical edges Iof the sections I3 when the two sections are aslower .edge of the body when their heads 23 are resting on the upper end ofthe body I2. It will be apparent how the pins 22 effectively connect the vertical edge portions of the sections I3 so that the assembly of the sections constitutes a rigid or unyielding reinforcement for the body I2.

The body I2 is adapted to shiftably engage the part 'of the drilling string on which the protector is arranged and projects from the string so that it may engage the well casing or the walls of the well bore to prevent engagement of adjacent projecting parts on the string, such as couplings or joints, from contacting with the well casing or the walls of the bore. The body I2 is resilient, being-formed of a rubber composition or the like. It is a feature of the invention that the protector is free to iioat in the rotary mud. As described above, the reinforcement I0 is formed of a very light weight metal and the assembly of the body I2 and reinforcement I0 constituting the protector has a specific gravity lower than the usual or typical rotary mud circulated through the well in the rotary method of well drilling. The body is an integral continuous' or unbroken member encasing or surrounding the reinforcement I0. The body I2 is tubular and is molded or vulcanized directly on to the reinforcement I0. In accordance with the invention the body I2 is moldyed on the reinforcement I0 when its sections I3 are connected by the pins 22 in the manner illustrated in Fig. 5 of the drawings. The resilient body I2 is proportioned so as to be shiftable on the part of the drilling string on which the protector is positioned and is comparatively thick so as to project a substantial distance from the said part of the drilling string and effectively prevent adjacent metallic parts of the string from contacting with the well casing or walls of the well bore. In the particular embodiment of the invention illustrated in the drawings, the exterior 25 of the body 'I2 is smooth and cylindrical, it

If desired or being understood that the body may be provided with any desirable or suitable form of external surface. The opposite ends of the body I2 may be iiat and normal to the longitudinall axis of the protector and may be provided with bevelled annular corner portions 26B.

In accordance with the broader aspects of the invention, the protector may be mounted on any part of the drilling string and may be rotatable and shiftable longitudinally on the string, or may be positioned between two shoulders or projecting parts so as to be held against longitudinal shifting but be free to rotate or to remain stationary relative to the rotating string. It may be found desirable to provide. a plurality of the protectors on the drilling string spaced so as to effectively prevent engagement of the projecting parts of the string with the casing or walls of the open well bore. Fig. l of the drawings illustrates the protectorl mounted on a connecting member or sub 26. The sub 26 is'provided at its upper end with a socket portion or enlarged portion 21, presenting at its lower end a downwardly facing shoulder 28 and provided at its upper end with a tapered socket 29 for receiving the screw threaded pin 30 of a tool joint section 3 I A socket portion 32 is provided on the lower end of the sub 26 and has va threaded socket 33 for receiving the threaded end portion of a length of drill pipe P. The upper end of the portion 32 presents an upwardly facing shoulder 34. The body I2 of the protector provided by the present invention surrounds the portion of the sub 26 between the spaced shoulders 28 and 34. In accordance with the particular application of the invention illustrated in Fig. 1, the body I2 is proportioned so that it mayhave little or no longitudinal movement on the sub 26 havingits opposite ends adjacent or in contact with the twoshoulders 28 and 34. The body I2 may be freely rotatable on the sub 26, that is, it may rotate relative to the sub or may not rotate during rotation of the string. In accordance with the invention, the body I2 is proportioned so as to project outwardly beyond the portions 21 and 32 of the sub and thus prevent engagement of these parts with the wall of the well bore. While we have illustrated the device mounted on a portion of the drilling string operating 'n an open part of the well, it is to be understood that the protector may be positioned on a part of the string operating within the well casmg.

Figs. 2, 3, and 4 of the drawings illustrate the body I2 of the protector on a sub 35. The sub 35 is provid-ed at its upper end with a tapered screw threaded pin 36.y adapted to be received by the socket of a tool joint section and is provided at its lower end with a tapered threaded socket 31 for receiving the pin of a tool joint section. An an-` nular enlargement 38 is provided on the base of the pin 36 and presents a downwardly facing shoulder 33. The lower portion 40 of the sub 35 is of enlarged diameter and its upper end presents an upwardly facing shoulder 4I. The sub 35 illustrated has a comparatively short upper enlarged portion 38. The body I2 of the protector is mounted on the sub 35 between the spaced opposing shoulders 39 and 4I. The shoulders operate to prevent longitudinal shifting of the protector, it being understood that the protector may be proportioned so as to have limited longitudinal movement on the sub if found desirable. The body I2 of the protector may be free to turn or rotate on the sub 35 or to remain stationary relative to the rotating sub 35. The resilient protector body I2 projects outwardly beyond the portions 38 and 40 of the sub and prevents their contact with the well casing or walls of the well bore.

Fig. 6 of the drawings illustrates a protector mounted on a length of drill pipe P'. of the protector is freely rotatable and shiftable longitudinally on the drill pipe P'. The couplings 43 on the opposite ends of ,the length of pipe P' operate to limit the longitudinal shifting of the body I2. distance from the drill pipe Pv', it positively pre- I vents engagement of the pipe and pipe couplings 43 with the well casing or walls of the well. The protector in being of less specific gravity than the rotary mud is free to float upon the pipe P to a 15 position immediately below the upper coupling where it effectively prevents contact of the coupling with the casing or wall of the well bore. In

accordance with the usual practice the circulation iluid or rotary mud is circulated downwardly 20 through the drilling string under pressure and discharges into the well at the lower end of the string to flow upwardly through the well. The rotary mud flowing upwardly through the well aids in moving the buoyant protector upon the 25 string and in maintaining it adjacent the lower end of a joint or'coupling 43.

In manufacturing or assembling the drill pipe protector provided by the invention, the two sections I3 of the reinforcement I0 are rst assem- 30 bled and connected together by means of the pins 22. The body I2 of rubber composition, or the like, is then vulcanized or molded directly on the sectional reinforcement I 0. After molding of the body I2 on the reinforcement, lthe pins 22 may 35 be pulled or driven out of the openings I8. The

heads 23 `of the pins may project from the upper end of the body I2 while the lower end portions 2 4 of the pins may project from the lower end of the body so that the pins are readily engageable 40 for withdrawal or removal. In arranging or assembling the protector on the part of the drilling string, either one or both of the pins 22 are re moved to permit the body I2 to be stretched or expanded. When one or both of the pins 22 have 45 been removed, the body I2 may be readily sprung over a projection or coupling on the string. Fig. 3 of the drawings illustrates the manner of passing or springing the body I2 over the enlarged portion sa of the sub 35. It win be apparent -50 how removal of the pins 22 permits the resilient/ body I2 to be stretched or expanded adjacent the lines of connection of the two reinforcement sections I3. After the body I2 has been passed or -55 sprung over the projection 38 or other projecting part its resiliency brings it back to its normal size so that the pin or pins 22 may be again passed or driven through the openings I8 to rigidly connect the reinforcement sections I 3. In practice, 60

where the shoulder or projecting part over which the body is to be sprung is comparatively short or comparatively small in diameter, it may be necessary to remove only one pin 22. Where one pin 22 is removed to allow spreading of the body 65 After the protector has been sprung into position between two projecting parts of the string, for example, between the two projecting portions 38 and 40 of the sub 35, the removed pin or pins 22 are again drivenvor passed through the openings I8 and the lower projecting portions 24 of the pins 75 The body I2 5 As the body I2 projects a substantial 10.

may be bent over to positively prevent accidental displacement of the pins.

The Substantially rigid or unyielding assembly of the two rigidly connected reinforcement lsections I3 effectively prevents spreading or expansion of the body I2 so that the body cannot become displaced from between the two projecting parts of the string. The reinforcement I0 does not in any way interfere with the free movement of the protector,.that is, it does not change the proportions of the body I2, and does project from the body so as to engage parts of the string, well casing, or the well bore. The sections I3 of the reinforcement are entirely embedded or encased in the material forming the body I2v and are therefore not subjected to distortion or breakage. The plurality of openings I4 and I5 in the sections I3 become filled with the material forming the body I2 when the body is molded on the reinforcement I0 so that the body is effectively bonded with the reinforcement and the portions ofthe body at the inner and outer sides of the sections I3 are integrally connected. When it becomes desirable or necessary to remove the protector from the drilling string, the lower end portion 24 of one or both of the pins 22 may beI straightened to permit the pin or pins to be driven out of the aligned openings I8. After removal of the pin or pins 22 the body I2 may beexpanded or stretched so as to be sprung over the projecting part such as the part 38 and thus removed from the sub or other part of the drilling string.

Fig. 7 of the' drawings illustrates a modified or alternative means Il for locking together the vertical edge portions of the reinforcement sections |3. The projecting and meshing parts I1 at the vertical edges of the sections are brought into mesh so that their openings IB are in vertical alignment. A pin is provided to cooperate with or pass through each set or series of aligned openings I8. In accordance with the form of the invention illustrated in Fig. 7 of the drawings, the pin 50 cooperates with-the meshing parts I1 in a manner so that it cannot become displaced, thereby dependably locking the sections I3 together. The pin 50 is provided at one vertical edge with projecting parts or portions 5I, and is provided at its opposite vertical edge with projecting portions 52.- The projecting portions 5I and 52 on the opposite vertical edges of the pin 50 are offset or staggered so as to be out of transverse or horizontal alignment. The projecting parts 5| and 52 arespaced and proportioned so as to be within the openings I8 of alternate portions I1. The lower corners 53 of the parts 5| and 52 are bevelled or inclined downwardly and inwardly.

When the pin 50 is passed into the openings I8 of the meshing parts I1, the projecting portions 5| and 52 operate to lock the pin against displacement. The lower end portion ,of the pin 50 that enters the opening I8 of the upper-most part I'I is free to pass through to the opening I3 of the next part I1. The lower corner of the lswermost projecting portion 52 then strikes 4the upper outer edge of the opening I8 in the second portion I'I, causing the resilient material forming the body I2 to yield or give. A suitable force yielding of the material of the body I2. From the above it will be apparent how the pin 5U may be driven through the openings I8 to the position illustrated in Fig. 7. After the pin 5U has been fully driven through the openings I8, the' upper ends of the projecting parts 5I and 52 are adapted to engage the lower ends of the meshing parts II to positively prevent Withdrawal of the pin. It is to be understood that pins 50 of the character illustrated in Fig. 7 of the drawings are to be used to connect the sections I3 when the protector is positioned on the drill pipe or drill string, and are not to be used when the sections I3 are initially connected for molding of the body I2 on the reinforcement I0. The means IIa illustrated in Fig. 7 is operable to dependably4 and positively lock the two reinforce-A ment sections I3 together to positively maintain the body I2 in its proper position on the drilling string.

Fig. 8 of the drawings illustrates a modification of the invention in which the opposite sides of the reinforcement sections I3a are roughened or provided with a plurality of projections or burrs 60. The projecting burrs 6U may be formed by punching or driving a suitable tool through the walls of the sections I3a which produces openings 6I in the sections. In accordance with the form of the invention illustrated in Fig. 8 of the drawings, the body I2a includes an outer tubular part 62 surrounding the sections I3 and an inner tubular part 63 within the sections' |33. The two parts 62 and 63 of the body I2 are Vulcanized together on to the sections |33. The provision of the openings 6I permits the effective vulcanizing together of the two body parts 62 and 63, and insures the proper bonding of the body parts 62 and 63 with the sections ISB. The projections or burrs 60 at the openings 6| become embedded in the body parts 62 and 63 and thus aid in connecting the body parts with the metallic reinforcing sections |39.

Having described only typical preferred forms v of our invention we do not wish to be restricted or limited to the specific forms or applications herein set forth, but wish to reserve to ourselves any variations or modifications that may appear to those skilled in the art or fall within the scope of the following claims.

Having described our invention, we claim:

1. A protective bearing device for use on a drilling string including, an unbroken annular body of resilient material adapted to surround a part of the string, a sectional reinforcement for the body, and means connecting the sections of the reinforcement to render the reinforcement substantially rigid, thereby preventing springing of the body over a projection on the string.

2. A protector for use on a drilling string having spaced projections, said protector including, an unbroken annular body of resilient material adapted to be sprung over one of said projections.

to Ya position on the string betweensaid projections, substantially rigid sections embedded in the body and having adjacent ends unconnected during said springing of the body over the projection, and means for connecting said ends of the sections to prevent subsequent expansion of the body.

3. A protector for use on a drilling string having spaced projections, said protector including, an unbroken annular body of resilient material adapted to be sprung over one of said projections to a position on the string between said projections, substantially rigid sections completely embedded in the body and having adjacent ends relatively movable during said springing of the body over said projection, and means for rigidly connecting said ends of the sections to prevent subsequent radial expansion of the body.

4. A well drilling string having longitudinally spaced projecting parts, a resilient continuous annular body adapted to be sprung over one of said parts to a position on th'e string between said parts, and means in the body for preventing radial expansion of the body after it has been positioned between said parts.

5. A well drilling string having longitudinally spaced projecting parts, a resilient continuous annular body adapted to be sprung over one of said parts to a position on the string between said parts, and means in the body for preventing radial expansion of the body after it has been positioned between said parts, said means including,

substantially rigid members embedded in the body, and means vfor connecting said members to form an annular rigid assembly.

6. A protector for use on a string of equipment operating in a well and having longitudinally spaced projecting parts, said protector including, a resilient continuous annular body adapt-ed to be sprung over one of said parts to a position on :le string between said parts, and means for preventing displacement of the body from between sad parts including substantially rigid members reinforcing the body, and removable eiements for v rigidly connecting said members whereby the members form .an annular assembly preventing radial expansion of the body.

7. A protector for use on a string of equipment operating in a` well and having longitudinally spaced projecting parts, said protector including, a resilient unbroken annular body adapted to be sprung over one of said parts to a position o n the string between said parts, and means for preventing displacement of the body from between .said parts including, substantially rigid arcuate members associated with the body, projections on the longitudinal edges of the members, and elements for cooperating with the projections on adjacent edges of the members to rigidly connect the members to form a rigid annular assembly.

8. A protector for use on a string of equipment operating in a w-e'll and having longitudinally spaced projecting parts, said protector including, a resilient unbroken annularI bodyA a resilient unbroken annular body adapted to bel sprung over one of said parts toa position on the string between said parts, and means for preventing displacement of the body from between said parts including, substantially rigid members molded in the body, projecting portions on the vertical edges of the members having vertical openings, said portions on adjacent edges of the member meshing one between the other, pins y adapted to be passed through the opening of the meshing portions to rigidly connect the members, and means for locking the pins in position.

l0. A protectory for use on a string of equipment operating in a well and having longitudinally spaced projecting parts, said protector including, a resilient continuous annular body adapted to be sprung over one of said parts to a position on the string between `said parts, a sectional annular reinforcement for the body and means for connecting the sections of the reina forcement after positioning of the body between Lsaid parts to prevent radial expansion of the body.

11. A protector for use on a string of equipment spaced projecting parts,.said protector including,

a resilient continuous annular body adapted to `'nular body adapted to be sprung over one of said parts to a position on the string vbetween said parts, and means in the body for preventingA radial expansion of the body after it has been positioned between said parts, said body being ro-` tatable relative to the string.

13. A protector for use on a string of equipment operating in a well and having longitudinally spaced projecting parts, said protector including, a resilient annular body adapted to be sprung over one of said parts to a position on the string between said parts, and means for preventing displacement of the body from between rsaid parts` including substantially rigid members molded in the body, projecting portions on thel members, and means for locking the pins in position, the last mentioned meansv including shoulders on the pins cooperating with said meshing portions and holding the pinsagainst longitudinal movement.

` 14. A protector for use on a string lofequipment having spaced projections including a continuous annular body of resilient material presenting an unbroken circumferential surface, the body being adapted to be sprung over a projection Vto a position on the .string between two` projections, and means for preventing radial expansion of the body after it has been positioned between projections.

CHARLES K. HOLT. IRA B. MARSH. JOHN B. MERRITT. 

